Circuit boards are utilized in many types of electronic equipment and it is often necessary, particularly in complex equipment, to interconnect the circuit boards into a module, and to interconnect modules into multiple circuit modules. For example, high speed electronic digital computers of the type produced by Cray Research, the assignee hereof, utilize circuit modules consisting of circuit boards mounted in close proximity on opposite sides of cooling plates. Such circuit modules are arranged in banks and it is therefore desirable to interconnect adjacent modules in a manner which permits convenient disconnection for service and reconnection after service, and which also air permits reverse stacking for testing.
A variety of connectors have been developed heretofore for electrically interconnecting two or more circuit boards in order to form a circuit module, however, the connectors of the prior art have not been altogether satisfactory for one reason or another. For example, one common approach has been to provide mating connectors at the edges of the circuit boards, however, this results in long circuit paths which in turn decrease circuit speed. Another approach has been to mount the male and female portions on opposing adjacent surfaces of the circuit boards to be connected. This approach only permits pairs of circuit boards to be interconnected, and is not adapted for reverse connection or for interconnecting in a chain. Another approach has been to provide each circuit board with a transverse pin and socket connector so that the pin or male portion is located on the opposite side from the socket or female portion. This approach permits reversal and allows chains of circuit boards to be connected together, however, precise placement and alignment of the connectors is necessary for proper connection. Such connectors are susceptible to damage and are both difficult and time consuming to repair or replace if damaged. Connectors of this type are not especially tolerant to misalignment and can easily become damaged during attempted connection if misaligned even slightly. In addition, the connectors of the prior art have not been particularly adapted to minimize twisting effects during disconnection or to release in a predictable, controlled manner so as to minimize possible damage to the connector.
A need has thus developed for a new and improved interconnected multiple circuit module with a connector of rugged construction which minimizes twisting and misalignment and which also facilitates connection over the shortest circuit paths and stacking of multiple circuit boards in reverse arrangement for testing and the like.